Making a figure-8 with an omni and a cardioid capsule.

[k brown]

Would independent front/rear pads make any sense? Or just an overall one...

Do you mean front/rear boards?

Idea is to have complete mic circuits for each capsule, going to a 5-pin XLR, so the two capsules can be mixed/processed externally (as with the Josephson C700A (not 'S').

 

[Khron]

Do you mean front/rear boards?

No, i meant attenuator pads.

 

[k brown]

No, i meant attenuator pads.

No, the idea is to do all the balancing of the capsules' levels outside the mic, to achieve any desired pattern.

 

[Khron]

No, the idea is to do all the balancing of the capsules' levels outside the mic, to achieve any desired pattern.

How's this, then?



(Ignore the silkscreen markings, haven't yet bothered with the "cosmetics"... )

 

[k brown]

Current plan:

Use this $18! ebay body with @kingkorg "kk12" for the cardioid and MXL603 capsule or sealed-back "kk12" for the omni. At 20mm, the "kk12" nicely splits the difference between the Josephson C700A's 16mm and 26mm capsules.

This body has a nice, tall grille head just high enough for the two capsules. Bought a pair a couple of years ago; https://www.ebay.com/itm/333952180682?itmmeta=01J2WE4A37WYVXS871DQDGV90F&hash=item4dc119e1ca:g:3WwAAOSwxT5gb~3l&itmprp=enc:AQAJAAAA0Jb0Tf8sNy+Aypj3lPA0yKsE1intVD60SgKMv1L4gNItgFUe5uaMJiJJiJeQ16e82I10ribRwAcy2hW0HGEeCsU1ZUSTD8jpCngyzysLC2a1cO+EKM4zmwxx0GS1Qqm5ZV4ovun8wO6SEzHPBPz19FVlRXgysC/+uhbalA7Fx6+MFX1CPp4U9W+d+OKtU7m1hUyhj3n5jk8OYB71MC3PpCkfkozH7t2gHWEz95O+uWEeWNqdHEOZizwrursLs1Sa1aWzEikyK0ciEp/fTGv61xw=|tkp:Bk9SR9yhkY6XZA

Almost exactly the same size as a C-37A.

Hoping I can replace the XLR's 3-pin insert with a 5-pin. Needs a proper capsule holder; comes with a cheap plastic one-piece job like the worst BM800 types.

Borrowing from Dave Royer, calling this "The Country Boy's C700A" (in general concept, anyway )

 

[k brown]

Capsules mounted ("kk12" + 'omni mod' "kk12" - both version 2).

These bodies are a fair amount of work; as you can see in the ebay listing, it comes completely disassembled, and all parts are covered with paint. Everywhere metal parts touch and need to electrically connect to each other and to ground, have to have the paint scraped away to make contact.

I'll probably attach all the head grille parts with electrically conductive epoxy.

Will probably end up cutting away some of the grill's top ring to obstruct the top capsule less (of course, the U47's grille ring was in front of the capsule a bit, too ).

 

[k brown]

Two other capsules that work extremely well for this because their responses are both so flat, are the Primo EM200 and EM273.

Plus, because they are both so small, they can be mounted very close together; therefore more consistent patterns in the vertical axis. Another advantage is that due to it's small size, the EM273 remains omnidirectional at higher frequencies, therefore when used to create a figure-8 the rear lobe won't be as dull-sounding as with the omni-adapted "kk12".

May not work so well with the Line Audio CM4 and Omni1 because his mods to the EM200 for the CM4 render it a subcardioid, but probably worth a try.

 

[k brown]

Also, now that both are again available, Primo EM21 and 23.

 

[RCAguy]

Do you mean front/rear boards?

Idea is to have complete mic circuits for each capsule, going to a 5-pin XLR, so the two capsules can be mixed/processed externally (as with the Josephson C700A (not 'S').

Josephson makes great mics. However this unit cannot alone make M-S, as the cardioid made from the omni + fig8 is 90deg off axis.

 

[k brown]

Josephson makes great mics. However this unit cannot alone make M-S, as the cardioid made from the omni + fig8 is 90deg off axis.

Don't know if your'e referring to the C700A, or the C700S.

Of course the 'A' can't make MS, it's not a stereo mic - it's a variable pattern mono mic.

As to the 'S', it can alone make MS on axis just fine; the bottom fig-8 capsule and the omni mix to make the forward-facing Mid cardioid (or whatever other pattern one would wish), and the top fig-8 capsule is the Side. Only mixing the top fig-8 with the omni would produce a cardioid 90 degrees off axis.

 

[RCAguy]

Don't know if your'e referring to the C700A, or the C700S.

Of course the 'A' can't make MS, it's not a stereo mic - it's a variable pattern mono mic.

As to the 'S', it alone does MS on axis just fine; the bottom fig-8 capsule and the omni mix to make the forward-facing Mid cardioid (or whatever other pattern one would wish), and the top fig-8 capsule is the Side. Only mixing the top fig-8 with the omni would produce a cardioid 90 degrees off axis.

Yes, the C with two 90deg fig8 elements can make MS. An issue may be the vertical separation of three diaphragms mounted high and tilted with different times of arrival between near v far sources.